As can be seen in FIG. 1A, to which reference is now made, a two-dimensional image sensor 10 captures a two-dimensional scene 12. Linear image sensors, on the other hand, provide a single line of sensors. They require significantly less bandwidth and computation than 2D image sensors. However, as shown in FIG. 1B to which reference is now made, a linear sensor 16 only views a portion (e.g. one line) of scene 12.
To utilize any kind of image sensor, whether 2D sensor 10 or linear sensor 16, focusing units 14 formed of lenses of various kinds, are usually placed in front of the sensors to focus light onto the sensors.
Reference is now made to FIG. 2, which illustrates a prior art measuring system used in a motion tracking system discussed in U.S. Pat. No. 6,324,296, entitled “BI-DISTRIBUTED-PROCESSING MOTION TRACKING SYSTEM FOR TRACKING INDIVIDUALLY MODULATED LIGHT”. The system of U.S. Pat. No. 6,324,296 has a linear sensor 16 and a cylindrical lens 20. As can be seen, linear sensor 16 is placed perpendicularly to cylindrical lens 20. Cylindrical lens 20 gathers light from a point P1 and provides it to sensor 16. The sensor of FIG. 2 is fixed in space and views a scene in which objects to be tracked move around.